1 files changed, 44 insertions, 0 deletions
diff --git a/graphics/surface-keycolored.cpp b/graphics/surface-keycolored.cpp
new file mode 100644
index 0000000000..86873a3944
--- /dev/null
+++ b/graphics/surface-keycolored.cpp
@@ -0,0 +1,44 @@
+#include "graphics/surface-keycolored.h"
+
+namespace Graphics {
+
+void SurfaceKeyColored::blit(Surface *surf_src, int16 x, int16 y, OverlayColor transparent) {
+	
+	if (bytesPerPixel != sizeof(OverlayColor) || surf_src->bytesPerPixel != sizeof(OverlayColor)) return ;
+
+	const OverlayColor *src = (const OverlayColor*)surf_src->pixels;
+	int blitW = surf_src->w;
+	int blitH = surf_src->h;
+
+	// clip co-ordinates
+	if (x < 0) {
+		blitW += x;
+		src -= x;
+		x = 0;
+	}
+	if (y < 0) {
+		blitH += y;
+		src -= y * surf_src->w;
+		y = 0;
+	}
+	if (blitW > w - x) blitW = w - x;
+	if (blitH > h - y) blitH = h - y;
+	if (blitW <= 0 || blitH <= 0)
+		return;
+
+	OverlayColor *dst = (OverlayColor*) getBasePtr(x, y);
+	int dstAdd = w - blitW;
+	int srcAdd = surf_src->w - blitW;
+
+	for (int i = 0; i < blitH; ++i) { 
+		for (int j = 0; j < blitW; ++j, ++dst, ++src) { 
+			OverlayColor col = *src;
+			if (col != transparent)
+				*dst = col;
+		}
+		dst += dstAdd;
+		src += srcAdd; 
+	}
+}
+
+} // end of namespace Graphics